Adventure Structure...... 1 C5. Human Infiltration Laboratory...... 20 Leveling Up...... 1 D. Biomass Reclamation Vat ...... 21 Using this Book ...... 1 D1. Empty Vat ...... 21 NPCs in the Adventure...... 1 E. Chamber of the Elder Shoggoth ...... 21 Using NPCs...... 1 F. Lighting Vortex ...... 22 Killing NPCs...... 1 Escape from the Elder Thing City...... 24 What if a Character Dies...... 2 Exit Pursued by Elder Things ...... 24 Using the Map...... 2 Chase Sequence Rules...... 24 Prologue...... 2 Conclusion...... 24 Intelligence...... 2 Leveling Up...... 26 Decisions...... 4 Chapter 3 . Cutting Off Chapter 1: For Want of the Serpent’s Head...... 27 a Lightning Gun ...... 5 Adventure Synopsis ...... 27 Adventure Synopsis ...... 5 Sidebar: Bringing NPCs Along...... 37 North to the Yithian City ...... 5 Serpent’s Head...... 27 The Winged Voicebox...... 5 If Defeated by Elder Things...... 28 Approaching the Mouth ...... 28 The Second Ritual on the Plateau . . . . . 6 Steam Tunnels...... 28 The Rearguard...... 6 A. The Mouth ...... 28 The Ritual...... 7 B. Temple of Yig ...... 29 The Flying Polyp Tower ...... 7 C. Stables ...... 29 Sidebar: Planned Obsolescence...... 7 D. Shantak Lair...... 32 Attacking Gehir...... 8 E. Sauna...... 32 Yithian Guard Tower...... 8 F. Empty Storage Room ...... 32 Making the Approach...... 9 G. Treasury...... 33 A. Entryway...... 10 H. Hydra Chamber ...... 33 B. Ground Floor...... 10 I. Barracks...... 33 C. Storage...... 10 J1. Kitchens...... 33 D. Second Floor...... 10 J2. Pantry ...... 33 E. Pterosentry Platforms...... 10 K. Tomb of the Serpent-Priests...... 33 F. Third Floor Hallway...... 12 L. Burning Heart...... 34 G. Command Center...... 12 M. Hatchery...... 35 H. Barracks...... 13 N. Council Chamber...... 35 I. Armory ...... 13 O. Alchemy Lab...... 35 J. High Security Armory...... 13 P. Dungeon...... 35 Exfiltration...... 13 Q. Portal Chamber...... 36 Leveling Up...... 14 South from the Karstlands...... 36 Chapter 2: The Shoggoth Creeps. . . 15 Sidebar: Simplified Travel ...... 36 Adventure Synopsis ...... 15 Mile 0 – The Yilani River...... 36 Mile 20 – The Old Goblin Village...... 37 Return to the Karstlands...... 15 Mile 60 – Fossil Digsite...... 37 Trail of Slime...... 15 Mile 85 – Fording the River...... 38 The Elder Thing City...... 16 Mile 100 – The Pass...... 38 The Shoggoth Factory ...... 16 General Tassala...... 38 A. Crescent Chambers...... 17 Battle at the Washout ...... 38 B. Hallway...... 17 Victory ...... 40 B1. Shoggoth Creation Hallway...... 17 Leveling Up...... 40 B2. City Construction Hallway ...... 17 B3. Mi-Go Battle Hallway...... 18 Chapter 4: Yig Snake Granddaddy. . . 41 B4. Aquatic Battle Hallway ...... 18 Adventure Synopsis ...... 41 B5. Shoggoth Rebellion Hallway ...... 18 Approaching Ventissa...... 41 C. Laboratories...... 18 If They Need Rest...... 41 SampleC1. Yithian Infiltration Laboratory ...... 18 file Sidebar: Teleportation...... 41 C2. Proto-Shoggoth Laboratory ...... 18 Dandelion’s Return...... 42 C3. Biotics Laboratory...... 20 Rescuing Nesmenhit...... 42 C4. Formless Spawn Laboratory ...... 20 If a Rest is Needed ...... 42 iii Anchorite’s Apotheosis...... 42 Debased Serpentfolk...... 69 Getting into Ventissa ...... 42 Dilophosaurus...... 70 The Walls...... 42 Yig-Touched Dilophosaurus ...... 71 The Gates ...... 42 lder hing arcomancer The River ...... 42 E T S ...... 72 Electro-Tank Ankylosaurus...... 73 A City Under Attack...... 44 Random Encounters...... 44 Hatzegopteryx...... 74 The Temple of Bastet ...... 44 Nohestan...... 75 Developer’s Note: NPCs in the City...... 45 Pterodactyl...... 76 The Hall of Curiosities...... 45 Pterosentry...... 77 The Citadel...... 46 erpentfolk inosaur ider The River Market...... 46 S D R ...... 78 The Laughing Lotus...... 46 Serpentfolk Infiltrator ...... 79 The Arena...... 46 Serpentfolk Lightning Warrior ...... 80 In the Presence of Yig...... 47 Serpentfolk Priest of Yig...... 82 Navigating the Arena ...... 47 Serpentfolk Trapper...... 83 The Stands ...... 47 Serpentfolk Warrior...... 84 The Waiting Rooms ...... 48 hoggoths The Lion Pit ...... 48 S ...... 85 Elder Shoggoth ...... 85 Confronting Gehir...... 48 Hulking Proto-Shoggoth...... 87 A Task for the NPCs...... 48 Yig has Risen! ...... 48 Siege-Claw Therizinosaurus...... 89 Prehistorification Ritual...... 48 Teleporting Velociraptor...... 90 Messengers of Yig and Champions of Bastet. . . . 48 Yithian General...... 91 Aftermath ...... 49 Alien Technology & Magic Items. . .93 The End...... 49 Adaptive Shield Array...... 93 If Gehir is Slain before Summoning Yig...... 49 Dagger of Metamorphic Venom...... 93 If the Heroes Slay Both Gehir and Yig...... 49 Die of Strange Geometries ...... 93 If Gehir Completes the Prehistorification Ritual before . Electro-Glaive...... 94 Dying ...... 50 Force Field Projector ...... 94 If the Heroes are Defeated while Fighting Yig. . . .50 Force Genade...... 94 If the Heroes are Defeated after Slaying Yig . . . . 50 Heat Pistol...... 94 Leveling Up...... 50 Matter Disruptor...... 95 Further Adventures in Yilan...... 50 Oil of Stone to Flesh...... 95 Welcome to Mesozoic Park...... 50 Psionic Lash...... 95 The Shoggoth Menace...... 50 Recharge Cell...... 95 The Yithian City ...... 50 Singularity Projector ...... 95 The Golden Tower...... 50 Stun Grenade ...... 96 NPCs and Items of Interest...... 51 Yithian Panoply...... 96 The Friendlies...... 51 Random Encounters...... 97 Maxx...... 52 Sarai Ninefingers...... 53 List of Maps Gunnar’s Team...... 54 Hexmap of Yilan ...... 3 Gunnar the Bold ...... 54 Yithian Guard Tower...... 11 Enivwenaye...... 56 Karstland Routes...... 16 The Rockbreakers...... 57 Shoggoth Factory ...... 19 Cathbad ...... 57 Serpent’s Head - Upper Level...... 30 ‘Shorty’ McCallam...... 58 Serpent’s Head - Lower Level ...... 31 Yitya Bolkorr...... 59 Ventissa...... 43 Dandelion...... 60 Arena ...... 49 Gehir...... 62 General Tassala...... 64 Nesmenhit ...... 66 SampleAllosaurus...... 67 file Hunter-Killer Allosaurus...... 67 Chasmosaurus...... 68 Sidebar: Tamed Dinosaurs...... 68 iv Act 4: The Ancient Ages Again A Cthulhu Mythos Adventure for 4 to 5 Characters of Levels 11-14

dventure tructure ture. Monster stat blocks, the Dread and Insanity A S mechanics, and the Yog-Sothothery skill from SPCM This final book of the adventure begins as the heroes will all be referenced in this adventure. are celebrating two major victories: they have de- Throughout this adventure, reference is made to stroyed the yithian mind-swap facility and slain the various monsters, NPCs, spells, and magic items. mighty nohestan, disrupting Gehir’s plans to summon Monster and NPC names may appear in bold, while Yig and revert all Yilan to its prehistoric state. But spell and magic item names will appear in italics. In soon the adventurers receive a vision from Gehir’s both cases, this is a prompt for you to look up the stat inner sanctum: the serpentfolk’s machinations have blocks in one of three places: the appendices in the uncovered another chance to summon Yig, and the back of this book, in SPCM, or in the Fifth Edition adventurers must act quickly to separate Gehir from System Reference Document or the Fifth Edition his allies. core books. If the reference is followed by a paren- Chapter 1 details a raid on a yithian outpost to thetical page number, the corresponding stat block acquire some of their powerful alien technology, and can be found on that page in the appendices. If the Chapter 2 lays out an attack on an Elder Thing shog- reference is to SPCM, it is followed parenthetically goth factory. It is up to the players which threat they by SPCM and the page number. The only place in will deal with first. Once they have played through this book where monsters from Acts 1-3 of Yig Snake both scenarios Gehir will be isolated, but nothing is Grandaddy can be found is in the appendix, and in more dangerous than a cornered serpent. As Gehir those cases, an additional note is provided indicat- accelerates his plans, the characters must take the ing the relevant installment. All other references to fight to him, assaulting his sanctum at Serpent’s monsters, spells, or magic items without such an Head in Chapter 3 only to find that he has fled south indication are available in the SRD. to Ventissa. The heroes’ final showdown with Gehir, Chapter 4, takes place in the city where the adven- NPCs in this Adventure ture began. Gehir seeks to summon Yig and sacrifice This adventure features a large cast of friendly NPC the city’s entire population for his eldritch ritual, and adventurers carried over from the previous book. De- the PCs—with the help of the Temple of Bastet—are pending on how the adventures in the previous book the only thing standing in their way. played out, some of these NPCs may be alive and in the PCs’ camp while others may be dead or in Gehir’s Leveling Up custody. Regardless, updated statistics for all of them At the end of each chapter of this book, the charac- are provided in the Appendix. ters should be given enough XP to level up. Ideal- ly, the party will reach 12th and 13th levels after Using NPCs completing Chapters 1 and 2 (not necessarily in that Having some NPCs survive will make things easier order), reach 14th level after completing Chapter 3, for the PCs and open up unique possibilities down and reach 15th level after completing the finale in the line. Their opinions and insights may be valuable Chapter 4. The loose structure of this book means to the PCs as they explore, research, and plan. The that a party might conceivably skip one or more NPCs presented in this book have a wide variety of acts; the GM should know (and make known to the skills and abilities, allowing them to fill in the gaps of players) that missing out on one section will make an under-strength adventuring party. They may pitch subsequent sections even harder. in during some of the more significant encounters, but the intent is not to have the NPCs tag along on Using this Book all the PCs’ adventures. The NPCs are less powerful Prior to running each adventure, you as the GM than the PCs, and there are always tasks they can be should familiarize yourself with the entire chapter. fulfilling “off-screen”. But should the players wish, one Sidebars, developer’s notes, Sandy’s Notes, and ap- or two NPCs might come along with them on any giv- pendices at the end of the book all provide additional en mission. For each NPC member of the party, add context, cues, and information to aid you in running 1 to your rolls when checking for random encounters. Yig Snake Granddaddy. This adventure makes extensive use of Sandy Pe- Killing NPCs Sampletersen’s Cthulhu Mythos (SPCM) for 5e, and having a file None of these NPC adventurers individually are copy of that book is essential to running this adven- critical to the plot, so the GM should feel no pres-

The Ancient Ages Again 1 sure to keep these characters alive. A canny GM can explaining the loss of the nohestan. “Its body was make use of the well-timed death of a beloved NPC to burnt. There is nothing to recover. I flew over it ratchet up the tension or raise the stakes of a partic- myself.” ular scene. If an NPC is present at a critical moment Gehir slams a scaly fist on the table, cracking in battle, they can also interpose themselves between the stone. “Without the nohestan, we cannot a wounded PC and an enemy’s killing blow, sacrific- summon Yig. The yithians are becoming too pow- ing their lives for the greater good. erful too quickly. We need the Mighty One to gain dominance in our alliance.” What if a Character Dies? “We must simply increase our rituals until another nohestan appears,” the one-eyed serpent- As the majority of this adventure takes place in the folk says, the words hissing. wilderness, far from civilization, the death of a player “Obviously. But without the Yithians’ mind- character raises the problem: where does their re- swap facility, sacrifices are hard to come by. Is the placement come from? If a PC ends up dying during portal to Ventissa ready?” this adventure, there are a few ways to proceed. A new voice from the doorway interrupts. “If I The player can always roll up a new character, but may, my lord…” A human in scholar’s robes steps they will need some reason to have been wandering into the light, his close-shaven head and brass- around Yilan before running into the PCs. Perhaps rimmed glasses striking a chord of unplaceable they were a remnant of another doomed expedition, familiarity. “There may be another option.” At this, one of the native elves of Yilan, or reinforcements the man transforms, human features morphing sent by the Cult of Bastet. Another option is for a into an ophidian visage. “In my position at the player to take over the character of one of the surviv- Hall of Curiosities in Ventissa, I have discovered ing NPC adventurers, working with the GM to roll up that one of the other masters has in his pos- a character of the same general class and abilities. session a fossil of a snake embedded in ancient This option is less ideal, as most players will prefer bronze. Might this be a young nohestan?” to make their own characters rather than inhabit a Gehir nods. “Well spotted, Steenis. Again, you pre-existing NPC. prove an invaluable asset. So the key to our plans lies in Ventissa. The city would make fine fodder Using the Map for my first great sacrifice.” The map on page 3 shows the area of Yilan in which “The Elder Things are hard at work on their parts of this adventure takes place. It is roughly shoggoth factory,” the scout reports. bound by the Karstlands to the south, the Stone “Excellent,” Gehir replies. “Armed with more Plateau to the north, the Yilani River to the West, yithian technology and the Elder Things’ shog- and the mountains to the East. There are 5 terrain goths, we will sweep through the city with ease.” types expressed on the map: grasslands, forest, hills, “Assuming the slugs don’t stab us in the back,” swamp, and rocklands (representing plateaus, mesas, the one-eyed serpentfolk mutters. karstland, and mountain ranges). “Never fear, General Tassala. I have a plan to Each hex on the map is 5 miles across. Charac- keep the yithians in line. Round up the rest of our ters traveling at a normal pace can traverse 4 hexes prisoners; we must pay our allies a visit.” per day. Traveling at a fast pace increases this to 5 “Very good, my lord.” hexes at the cost of a -5 penalty to passive Perception “And General, have you yet located the Sphere checks, while traveling at a slow pace decreases it of Nath?” to 3 hexes per day while allowing the party to travel “That was to be my next announcement, my stealthily. Each hex of swamp or rocklands terrain lord. I—” Tassala turns to grab something but counts as 2 hexes for the purposes of travel times. stops as her eye catches yours. Swift as a striking The GM should feel free to use their preferred rule- adder, she grabs a spear and hurls it at you. You set to cover activity while traveling including foraging, attempt to bound away, but the dream suddenly hunting, navigation, and downtime. ends. You awake in the dim morning light, heart pounding and short of breath. You don’t know if Dandelion made it out safely, but the dream she Prologue sent you makes it clear that Gehir is still a force to be reckoned with, and you must act quickly to A dream: stop him from achieving his goals. You lurk in the shadows of some dimly lit cavern. From your cat’s-eye perspective, you see Gehir Intelligence in all his abominable glory—a living embodiment of Yig’s will in the mortal realm. He stands at one There are several pieces of information from the Sampledream that the PCs may decide fileto pursue. end of a stone table. To his right stands a scarred, one-eyed serpentfolk in gleaming multicolored Master Steenis. The serpentfolk spy is the curator armor. To his left, a scout wrapped in leathers is of the nature gallery in the Hall of Curiosities in

2 The Ancient Ages Again Sample file

The Ancient Ages Again 3 Ventissa; characters who interacted with him there Attack Gehir are able to recognize him in the clarity of the waking If the PCs decide to attack Gehir directly, proceed to world. the Serpent’s Head section of Chapter 3: Cutting off Shoggoths. Characters who succeed on a DC 13 . Wisdom (Yog-Sothothery) or DC 20 Intelligence (Ar- the Serpent’s Head cana) check know that shoggoths are massive lumps Rush to Ventissa of magically engineered protoplasm used as powerful weapons of war by the Elder Things and other If the PCs decide to make a run toward Ventissa, ancient races. Characters exceeding the DC by 4 or proceed to the South from the Karstlands section of more learn about the shoggoth’s abilities, resistances, Chapter 3: Cutting off the Serpent’s Head. immunities, and vulnerabilities (SPCM 371). Char- acters can also investigate shoggoths in any of the Mythos texts they possess (see Book 2, Chapter 2). Sphere of Nath. Characters who succeed on a DC 16 Wisdom (Yog-Sothothery) or DC 23 Intelli- gence (Arcana) check, or who succeed on a check to research the subject in one of their Mythos texts, know that a sphere of Nath (SPCM 129) is a potent magic item that lets a spellcaster draw on the inher- ent power of distant locations while casting spells. Characters who know this and who succeed on a DC 15 Intelligence (Arcana) check can figure out that possession of a sphere of Nath would let Gehir perform his prehistorification ritual anywhere, without needing to be at the junction of two ley lines.

Decisions The PCs now have four options: attack the Elder Things’ shoggoth factory, find some way to disrupt the yithians and keep them from helping Gehir, attack Gehir directly, or make a break for Ventissa. The lat- ter two options should be less attractive, as attacking Gehir without first separating him from his allies might be prohibitively difficult and goes against all of Dandelion’s prior advice, while escaping south to Ventissa not only requires bypassing the Elder Thing lands but would leave Gehir free to build up his forces at his leisure. The first two options both have the advantage of weakening Gehir’s tenuous alliance. Attacking the yithians has the added benefit of providing an opportunity to seize some of their powerful weaponry, which would surely make any subsequent steps easier to accomplish. The PCs may come to some or all of these con- clusions on their own, and they should identify the following four courses of action. NPCs (if any are present) can point out anything they missed, and one or more NPCs might have a strong opinion about which course they should take; don’t make the deci- sion for the players, but make it clearly a tricky one.

Attack the Yithians If the PCs decide to attack the yithians, proceed to Chapter 1: For Want of a Lightning Gun. SampleAttack the Elder Things file If the PCs decide to attack the Elder Things, proceed to Chapter 2: The Shoggoth Creeps.

4 The Ancient Ages Again Chapter 1: For Want of a Lightning Gun

Adventure Synopsis North to the Yithian City With the guidance of a cyborg pterodactyl sent by Depending on where in Yilan the PCs are, it may take their tenuous ally Xuxuxlu, our heroes trek north- several in-game days to reach the yithian lands in the wards into Yithian lands in hopes of obtaining some north. As usual when adventuring in the wilderness, valuable technology. refer to the hexmap of Yilan on page 3 and determine When they arrive, they find that Gehir is already random encounters as normal. there, preparing to perform a sacrifice. With legions of serpentfolk and yithians present, the adventurers The Winged Voicebox can only watch as Gehir slaughters numerous prison- When the PCs decide to go north to the yithian city ers, restoring a great swath of the prehistoric yithian (or when the GM decides to nudge them in that direc- city. But Gehir’s ritual has also restored a flying polyp tion), a strange creature appears and speaks to them. tower, and the ancient enemies of the yithians pour forth from their black spire, wreaking havoc on the Without warning, a small, leather-winged mon- proceedings. strosity alights on a nearby branch. It looks much In the confusion, the heroes break into a yithian like Gehir’s familiar, Turu, but it has been phys- guard tower, battling members of the Great Race and ically altered, much like the yithians’ dinosaurs. their dinosaur slaves and seizing a veritable armory The top of its head has been replaced with a of yithian weapons and technology. Making their es- brass speaking horn, while a second appendage cape, the PCs must fight their way past the dreaded has been added to its shoulders, this one a ten- Sampleflying polyps, putting their new weapons to the test. file tacle tipped with a trio of black eyes. Across its torso, a fleshy seam like a second mouth opens to reveal a tiny hand which tosses something at

For Want of a Lightning Gun 5 your feet. It is a golden badge set with a faceted guidance with this winged voicebox.” orange topaz. “Greetings, bipeds!” says a tinny ◊ “You may believe yourselves voice echoing from the creature’s head-trumpet. A word of caution. to be invincible, but the Great Race is powerful “It is I, Xuxuxlu. I promised you weapons and I beyond your comprehension. You should try to en- am here to deliver.” gage no more than two of our number at a time, or the combat will likely not go in your favor. For that The creature is a cybernetically modified pterodactyl reason, I also do not recommend that you loiter called a winged voicebox (use the stats pterodactyl too long in the tower: even a minor counterattack on page 76) remotely controlled by Xuxuxlu. The from soldiers of the Great Race could mean your rebel yithian can see, hear, and speak through the deaths.” pterodactyl. Xuxuxlu has identified an opportunity Xuxuxlu, through his “winged voicebox” will accom- for the PCs to seize some yithian technology with pany the PCs in their northward venture, providing which to fight Gehir. He can speak on that and other guidance where he can, urging caution when appro- subjects, using the following examples as a guide: priate, and periodically expressing his supercilious ◊ What’s the plan? “I have identified the structure disdain for their “inferior” bodies. within our city that will be the easiest for substan- dard lifeforms such as yourselves to attack. It is a guard tower in the southeast of our city. It has for- The Second Ritual on the midable defenses, but it is far removed from other lateau buildings so you will face less interference from P others of the Great Race. Once inside, you should When the PCs arrive in the hex that contains the be able to equip yourself with as much of our tech- yithian city, the settlement itself is concealed from nology as you can carry.” view by a low, grassy ridge. ◊ What of Gehir? Xuxuxlu’s ptero- “There is one further dactyl flies up to factor that should make scout the area and re- this raid possible for you: ports back to the char- I have received word acters within a few through my sources that minutes. Xuxuxlu tells Gehir is coming north the characters that soon. Thanks to your there are a serpentfolk destruction of the mind and a yithian waiting in swap facility, our ruling a valley on the other side faction and Gehir agree that of the ridge. Beyond the he must restore more of our valley, Gehir and a force of city for the mutual benefit of serpentfolk have gathered our alliance. Restoring more of in the center of a semicircular the city will likely cause another clearing just outside the city, small civil war within the Great where a crowd of yithians has Race over whether to remain allied with come to watch the spectacle. the serpentfolk. During the confusion, Far to the right of that clearing stands your raid on the guard tower will go relatively the guard tower that is the target of the unnoticed.” characters’ raid. ◊ So… are you a pterodactyl now? “When the The Rearguard guards attacked us in the facility, I escaped by mind-swapping into another body. This creature The serpentfolk and yithian in the next valley before you is merely a tool I can use to communi- can be avoided with a successful group DC 13 Dex- cate with you remotely.” terity (Stealth) check. At the GM’s discretion, if the ◊ What kind of weapons will we get? “The guard characters were being particularly loud or noticeable tower should be well equipped with weapons and before or during Xuxuxlu’s scouting flight, the ene- technology, much of which will be familiar to you mies may already be aware of the PCs and preparing from your time in the mind swap facility. I do not to attack. The ridge is 20 feet high and gently sloped know the exact inventory of the tower, but it will enough as to not impede movement. The valley be well worth your trouble.” between this and the next ridge is 100 feet wide. The valley is both the easiest location from which to view ◊ Will you be helping us attack the tower? “I will the ritual and the safest way to approach the guard Samplebe coordinating resistance efforts, executing plans file tower. to help my faction achieve power during the confu- Creatures. There is one past yithian (SPCM 398) sion that will immediately follow the restoration. without a lightning gun, and a serpentfolk warrior But I will be able to keep track of you and offer 6 For Want of a Lightning Gun